Ricardo is 3 years older than courtney. in 5 years the sum of their ages will be 81. how old is ricardo now?

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.

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g

Given sin28.4=.4756, cos28.4=.8796, and tan28.4=.5407 find the cot of 61.6