4. Consider the following groups G and H, K

Solve correctly ASAP Do both parts

Extracted text: 4. Consider the following groups G and H, K < g.="" if="" g="" is="" isomorphic="" to="" h="" ×="" k,="" give="" an="" isomorphism="" y="" :="" g="" →="" h="" ×="" k.="" if="" not,="" say="" why="" g="" and="" h="" ×="" k="" cannot="" be="" isomorphic.="" (a)="" g="R*," h="{1," –1},="" k="R+" (b)="" g="D4," h="{1,r," r²,="" r³},="" k="{1," s}="">