What is the correct shape for the Images above (zoom in for better view)

if you don't know please don't put anything random for points:)

O Tetrahedral
O Bent
O Trigonal Planar
O Linear
O Trigonal Pyramidal​

Atank contains 240 liters of fluid in which 10 grams of salt is dissolved. brine containing 1 gram of salt per liter is then pumped into the tank at a rate of 6 l/min; the well-mixed solution is pumped out at the same rate. find the number a(t) of grams of salt in the tank at time t.

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

What is the number of atoms in 3.54 mol s