If the sixth term in the binomial expansion of $\left(x^{-\frac{8}{3}}+x^2 \log _{10} x\right)^8$ is 5600, then what is the value of x ? 

How many terms are there in the expansion of (3x - y)⁴(x + 3y)⁴ ?  

p, q, r and s are in AP such that p + s = 8 and qr = 15. What is the difference between largest and smallest numbers ?  

Consider the following statements for a fixed natural number n:

1. C(n, r) is greatest if n = 2r

2. C(n, r) is greatest if n = 2r - 1 and n = 2r + 1 

Which of the statements given above is/are correct ?