A piece of chocolate cake has 400 calories in it. Anita cut a 1 kg of cake for her birthday which has about 35 pieces. How many calories does the cake has in total?

Question

$\begin{array}{11} (a)\; 17000 \\ (b)\; 15000 \\ (c)\; 12000 \\ (d)\; 14000 \end{array}$