How many dots are in the 4th step

Answer:
each layer we add 2 dots so in next layer there is 8 added dots totalling 20 dots in 4th step
Step-by-step explanation:
step 3 shows 1 layer of 2 , 1 layer of 4, and 1 layer of 6 totalling 12 dots
step 4 would be 1 layer of 2, 1 layer of 4, 1 layer of 6, and 1 layer of 8 totalling 20 dots