Exercițiul 3. Este urgent

a) MN=MQ-NQ=MQ-NR-RQ=10cm-4cm-4cm=2cm
b) PR=NR-NP=4cm-1cm=3cm
c) MR=MQ-RQ=10cm-4cm=6cm
d) PQ=PR+RQ=3cm+4cm=7cm