Let's do this.
First you have to analyse the informations given.
It says : c = 3 and d = 4.
Now you merely have to substitute these two numbers in the expression given.
It gives :
2d³ + 3c² + 5
= 2(4)³ + 3(3)² + 5
= 2*64 + 3*9 + 5
= 128 + 27 + 5
= 160.
In short, the answer is 160.
Hope this helps !
Photon