$1\mathrm{.}7$ What is the effect of the following sequence of RTL instructions? Describe each one individually and state the overall effect of these operations. Note that the notation $x$ means the contents of memory location $x.$

a$.[5]larr2$

b$.[6]larr12$

c$.[7]larr[5]+[6]$

d$.[6]larr[7]+4$

e$.[5]larr[[5]+4]$