[Q]: Which of the following solutions is better for the following goal:
To clean rust stains off of the bath tub.

[A]: Use half a grapefruit and salt. Sprinkle about a 1/4 cup of kosher salt on a halved grapefruit.

[Q]: Which of the following solutions is better for the following goal:
How to make Lemon slushies at home.

[A]: Use Ice tray to freeze Lemonade. Use from carton at grocery stores. When lemon (Ice) is frozen, place ice cubes in a blender. Mix on low at first then raise speed. Add 1/2 cup fresh lemon juice with 1/4 cup sugar. When blended serve in a dish.

[Q]: Which of the following solutions is better for the following goal:
Patch holes in tarp to make waterproof.

[A]: You can use duct tape to patch holes in the tarp to make waterproof. Start at one end of tarp and hold up to sun looking from the bottom any holes will show visible light where they are located mark with a marker , use one darker or lighter than the tarp color. When finish patch holes on a flat surface appling the duct tape and smoothing out with your hand.

[Q]: Which of the following solutions is better for the following goal:
Attach the wood together for the box

[A]:
Place the pieces together with wood glue between the pieces and fix with a clamp to dry