Alejandro says that swimming 12 laps every 8 minute is a constant speed of 2/3 laps per minute. is his calculated speed was correct or incorrect ?pls help me

All per-unit concepts rely on ratios,meaning,to provide a type of measurement

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?

7+(3n++8) what is the answer to this?