On the first day of her 5-day trip, miss gordon drove 435 km in 5.3 hours. on the next three days, she drove 80.78 kilometers in 65 minutes. on the fifth day, she drove 880 meters. how many kilometers did she drive in all?

This is so hard and it’s for a test

Can someone check if i did this correct. it’s number 4 if you’re wondering.

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.