What is the domain of this function ? What is the range of this function ?

Ihave a 69 and an 82. the 69 is worth 40% of my grade and the 82 is worth 15%. can someone tell me my current average grade.

Roger and natalie travel in similar cars. roger's car drives the two miles to school in 7.5 minutes. natalie drives the same distance in the opposite direction but in only 6.5 minutes. what is true of their velocities?

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?