patient receives M milligrams of a certain drug each day. Each day the body eliminates 25% of the amount of drug present in the system. Determine the value of the maintenance dose M such that after many days approximately 20 milligrams of the drug is present immediately before a dose is given.​

4+4+2x

or

2x+8

step-by-step explanation:

4+3x is the answer

hope you got it

large crystals result from very slow cooling.

evaporation of water: this would produce an evaporite which is a sedimentary rock. like a salt pan in a desert. not possible to have volcanic rocks originate this way.

crystalization in molten earth: slow cooling over time. (hundreds to millions of years)

crystalization at earth's surface: this results in fast cooling. (a few hours to a few months or years)

crystalization from cooling off hot water: that would be a hydrothermal deposit. while associated with volcanics they are not volcanic rocks themselves and usually occur fairly rapidly.