18 A rock is dropped from a hot air balloon at a height of 100 meters. The rock's
height from the ground in meters, h(t), is modeled by the formula
h(t) = -4.9% + 100, where t is the time in seconds.
What is the average rate of change in m/s of the height of the rock between 2 and
4 seconds?

The table shows a pattern of exponents. what is the pattern as the exponents decrease?

Let hh represent the number of hummingbirds and ss represent the number of sunbirds that must pollinate the colony so it can survive until next year. 6h+4s > 746h+4s> 74 this year, 88 hummingbirds pollinated the colony. what is the least number of sunbirds that must pollinate the colony to ensure that it will survive until next year?

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?