OK, let's work through this together. We're starting with 856 and we're going to multiply it by 4, which means we add 856 to itself 4 times.
Step 1: 0 + 856 = 856
Step 2: 856 + 856 = 1712
Step 3: 1712 + 856 = 2568
Step 4: 2568 + 856 = 3424

So, 856*4 = 3424