I need help with sql exercise.

Concept Question 1 -Index Placement Consider the following ERD in Figure 1 ITEM RENTAL TAPE PK RENT NUM PK FK1 CUS NUM FK2 TAPE CODE TAPE COPY TAPE NAME TAPE CHARGE CUS LNAME RENT DATE OUT RENT COPY RENT CHG DAY RENT DATE_RETURN RENT CHARGE Figure 1 Also, assume the following query is frequently run... SELECT CUS NUM, RENT NUM FROM ITEM JOIN RENTAL ON ITEM . CUS NUM RENTAL. CUS NUM WHERE CUS LNAMESMITH' Concept Question 1.1: Specify where indexes should be placed and if the index should be a unique or non-unique index. Explain your response Concept Question 1 -Index Placement Consider the following ERD in Figure 1 ITEM RENTAL TAPE PK RENT NUM PK FK1 CUS NUM FK2 TAPE CODE TAPE COPY TAPE NAME TAPE CHARGE CUS LNAME RENT DATE OUT RENT COPY RENT CHG DAY RENT DATE_RETURN RENT CHARGE Figure 1 Also, assume the following query is frequently run... SELECT CUS NUM, RENT NUM FROM ITEM JOIN RENTAL ON ITEM . CUS NUM RENTAL. CUS NUM WHERE CUS LNAMESMITH' Concept Question 1.1: Specify where indexes should be placed and if the index should be a unique or non-unique index. Explain your response