On the manuela question, why did y’all multiply 300 times 25?

What is the volume of a rectangular prism if the length is 10.4 mm the width is 5 mm in the height is 8 mm

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.