There is a few questions but im stuck on this one. please help Why is it important to know how to calculate with percents?

Calculating percentages are important as they apply to real life activities. For example, shopping. If you are on a budget and you want to know how much your total is with tax, you can convert the decimal for the tax, turn it into a percent and add it to your total. Another example is eating at a restaurant. A good tip is 15-20% so you can calculate this and add it to your price.

Step-by-step explanation:

d. millimeters per hour.

step-by-step explanation:

we are given that,

carlo used a rain gauge to measure the amount of water his lawn is receiving from the sprinklers.

since, according to the options, we see that,

water cannot be measured by 'miles per hour', 'meters per second' and 'grams per seconds'.

we get that, the water can be measured by 'millimeters per hour'.

hence, the appropriate rate for describing the amount of water is 'millimeters per hour'.