K is square integer

[gmat740]

If K is a positive integer, is K the square of an integer?
(1) K is divisible by 4
(2) K is divisible by exactly 4 different prime numbers


I always screw up these kinds of factors & integer questions. Any advice for solving these kinds of questions?

Thanks

[tohellandback]

IMO E
sorry if there is a typo. I am posting from my phone.
1) 12- not a square
16- a square
not suff

2) for the number to be a square the prime factors should have rcen powers.
Not suff.
Combined, we still need to know the powers for those prime factors