20-ft long w21x48 (fy= 60 ksi) simply-supported beam is subjected to a point service load p at midspan. lateral supports exist only at the beam ends. the service load consists of 70% live load and 30% dead load. solve the entire problem as per the lrfd method of the 2016 aisc. a. check lb requirements for the beam (5) b. indicate the lateral support condition (i. e., the range of lb) as evidenced by the detailed calculation; must show and box lp (in ft. to the second decimal place) and lr(in ft. to the first decimalplace)values.(10)c. identify which limit states should be considered to determine mn(nominal moment strength) andcalculate and box the mnvalue for each limit state, in kip-ft to the third decimal place. then, determineandboxma(available moment strength) also in kip-ft to the third decimal place. (20)d. determine and box the maximum p for bending, in kips to the third decimal place (10)e. determine and box va(available shear strength) in kips to the third decimal place (10)