Answer:
D. The expression is
. It takes 40 minutes to shape and fire 10 pots.
Step-by-step explanation:
Let the number of pots in a batch = p
Now, one pot takes 3 minutes to get in a shape.
Then, 'p' pots will take
minutes to get in a shape.
Also, it takes 10 minutes to fire one batch of pots.
Thus, the expression for the time taken to form one batch of pots = 
So, when number of pots = 10 i.e. p= 10.
Time taken to fire the pots =
= 30+10 = 40
That is, 'It takes 40 minutes to shape and fire 10 pots'.
Thus, option D is correct.