1 )  2+2^6/20=2+64/20=2+32/10=2+3,2=5,2

2 ) 7^3-40=343-40=303

3 ) 4*84-300^3=336-27000000=-26999664

4)(56/30:30/29)^4=(56/30*29/30)^4=(1624/900)^4=(406/225)^4=406^4/225^4