Differential equation for the variation of amountof sait ‘x’ in a tank is given by :$$(\frac{dx}{dt} )+ (\frac{x}{20})$$ = 10. where x is in kg and t is in minutes. Assuming that at time zero thereis no salt in the tank, find the time at which the amountofsalt increases to 100kg

A

100 ln 2

B

50 ln2

C

20 ln 2

D

10 ln 2