A tank contains 70 kg of salt and 1000 L of water. Water containing 0.4kgL of salt enters the tank at the rate 16 Lmin. The solution is mixed and drains from the tank at the rate 4 Lmin. A(t) is the amount of salt in the tank at time t measured in kilograms.

Explanation:

A(t) is the amount of salt in the tank at time t, measured in kilograms.

A(0) = 70

rate in - rate out

=0.4* 16 - (A/1000)*4

=   kg/min

A(0) = 70

-ln (1600 - 70) = 0/250  + C

-7.33 =  C

i believe the answer is a.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.