A rock is thrown upward from the surface of Mars with an initial velocity of 50 feet per second. The height of a rock can be modeled by the: h(t)=-6.5t^2+50th(t)=−6.5t 2 +50t. How long does it take the rock to fall back to the surface of Mars? Round to two decimal places.

9.23secs

Step-by-step explanation:

Given the height of the rock modeled by the equation;

h(t)=-6.5t^2+50t

The rock falls back to the surface of the Mars at when the height is zero i.e h(t) = 0

Substitute into the formula and get the time t

h(t)=-6.5t^2+50t

0 = -6.5t^2+50t

6.5t^2 = 50t

6.5t = 50

t = 50/6.5

t = 9.23secs

Hence the rock fall back to the surface of the Mars after 9.23secs

step-by-step explanation:

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.