(a) 3x3−4xy+z2−3x+3y
Yes. Because there are no negative or fractional powers for the variables.
(b) 3a2b−4√b3+b2
No. Because, there is a square root over b. So, there is fractional power over a variable.
(c) 52x2−4yz−56x2
Yes. Because although the coefficient 52 and −56 are fractional coefficients, the powers of variables are all whole numbers.
(d) 3p3−4q23+pqr+3pq
No. Because there is a fractional power over q.