What was the robotic vehicle opportunity designed to do?

a. probe beneath the moon’s surface for signs of volcanic activity

b .map the contours of craters and valleys on the moon

c. determine the chemical composition of rocks and soil on mars

d. measure precipitation on mars

C. determine the chemical composition of rocks and soil on Mars    

Explanation:

Opportunity-Robotic vehicle was sent on Mars in 2003 and it became active on its surface from 2004 to mid 2008. Opportunity is also known as Mars Exploration Rover B (MER-B).

The main goals of this mission were:

1. To find if there is any scope for life to exist on the planet (to find presence of water)

2. To find about climate and geology of the planet so that humans can be sent in future on the planet.

This includes the determining the chemical composition of the rocks and soil on Mars.

explanation:

the formula mass of a molecule or a compound is the sum of the atomic weights of the atoms in its empirical formula

(that's what i know about formula mass)