Q: If you are using a roller suitcase, place the soles of your heaviest shoes flat against the walls of the suitcase near the wheels. Line the walls of your roller suitcase with any additional shoes. Make sure to place the soles of the shoes flat against the walls of the suitcase as well. Instead of placing bulky shoes next to each other, pack them separately to utilize the space in your suitcase. If you have to place them side by side, then arrange them heel to toe. For example, place boots and wedges heel to toe if you cannot pack them separately. Tuck flats and flip flops inside pockets or extra space when you are finished packing. You could also place them on top of your clothes once you are finished packing.
A: Place your shoes at the bottom of your suitcase. Pack bulky shoes separately. Pack flats and flip-flops last.

Q: Try this method only if you want to kill weeds in an area where you do not plan to grow anything for several years -- perhaps around paving stones and in pavement cracks. Salt kills the weeds by dehydrating them and absorbs into the ground, preventing all plant growth. You can apply salt in one of two ways:  Dissolve 1/2 c (120 mL) salt into enough warm or hot water to fill your spray bottle. Apply the salt dry. Simply sprinkle the salt on the weeds you want to kill. This works particularly well on garden paths and along lawn edgings. Dump a large pot of boiling water on your weeds if there are no other plants close by. Since boiling water kills the weeds by literally burning them, don't use it around your other plants. Boiling water can be very effective, especially on young weeds, and results are typically immediate.  You might have to repeat this several times over multiple days to sufficiently kill all the weeds. Add 1 tbsp (15 g) of table salt to the boiling water to make an even stronger solution. Mix 10 ounces (280 g) of borax  and 2.5 gallons (9.5 L) of water together thoroughly. Use a garden sprayer to apply the solution to the weeds. Be careful not to saturate the soil as it could damage plants you want to keep.  Wear gloves and glasses while you handle the solution, since it may cause skin irritation. Never use this solution to control weeds in a vegetable or flower garden; it will damage veggies and flowers.
A: Use rock salt or table salt as a weed killer. Kill the weeds with boiling water. Spray a mixture of borax and water on the weeds.

Q: The physics concept of acceleration doesn't always match how we would use the term in everyday life. Every acceleration has a direction, usually represented as positive if it's UP or RIGHT, and negative if DOWN or LEFT. See if your answer makes sense based on this breakdown:   Behavior of a Car How is Velocity Changing? Direction of Acceleration    Driver moving right (+) hits gas pedal    + → ++ (more positive)       positive     Driver moving right (+) hits brakes    ++ → + (less positive)       negative     Driver moving left (-) hits gas pedal    - → -- (more negative)       negative     Driver moving left (-) hits brakes    -- → - (less negative)       positive     Driver moves at constant velocity    remains the same       acceleration is zero Remember, a force only causes acceleration in the direction of the force. Some problems may try to trick you with irrelevant values.  Example Problem: A toy boat with mass 10kg is accelerating north at 2 m/s2. A wind blowing due west exerts a force of 100 Newtons on the boat. What is the boat's new northward acceleration? Solution: Because the force is perpendicular to the direction of motion, it does not have an effect on motion in that direction. The boat continues to accelerate north at 2 m/s2. If more than one force acts on an object, combine them into a net force before you calculate acceleration. For a problem in two dimensions, this looks something like this:  Example Problem: April is pulling a 400 kg container right with a force of 150 newtons. Bob stand on the left of the container and pushes with a force of 200 newtons. A wind blowing left exerts a force of 10 newtons. What is the acceleration of the container? Solution: This problem uses tricky language to try and catch you. Draw a diagram and you'll see the forces are 150 newtons right, 200 newtons right, and 10 newtons left. If "right" is the positive direction, the net force is 150 + 200 - 10 = 340 newtons. Acceleration = F / m = 340 newtons / 400 kg = 0.85 m/s2.
A: Understand the Direction of Acceleration. Understand the Direction of Force. Understand Net Force.

Q: Etching cream is not recommended for large surface areas because of its potentially toxic fumes. Acid washing is another method of etching glass, but it is best left to professionals due to the potentially toxic nature of the ingredients used in the process. Sandblasting, etching and acid washing are all permanent and cannot be reversed
A:
Remove window glass from frame, wash and allow to dry. Rent a sandblaster and buy sand/grit from the rental store. Protect the work area with heavy canvas drop cloths and don protective eye goggles, work gloves and face mask. Place window glass in center of drop cloth and follow manufacturer's directions carefully to etch the entire surface of the glass. Clean window glass of excess grit, and replace glass in window frame.