4.27 Problems in this exercise refer to the following sequence of instructions, and assume that it is executed on a five-stage pipelined datapath: ADD X5, X2. X1 LDUR X3, [X5, #4] LDUR X2, [X2, #0 ] ORR X3. X5, X3 STUR X3, [X5, #0] 4.27.4 [20] If there is forwarding, for the first seven cycles during the execution of this code, specify which signals are asserted in each cycle by hazard detection and forwarding units in Figure 4.59. 4.27.5 [10 If there is no forwarding, what new input and output signals do we need for the hazard detection unit in Figure 4.59? Using this instruction sequence as an example, explain why each signal is needed. 4.27.6 [20] For the new hazard detection unit from 4.26.5, specify which output signals it asserts in each of the first five cycles during the execution of this code