How to solve (4) explain clearly plz with SUMIF equations

Calculate the followings by using sumit or sumits and pivot table W N Date Region SalesRep Sales Region Total Sales 2) Date Total Sales SalesRep Total Sales 10/20/19 West Gigi $620 Northwest $9,582 10/20/19 5710 June 7622 10/20/19 Northwest Gig $484 Southwest $6,234 10/21/19 3038 Chin 7880 10/21/19 West Freddy $376 West $12,430 10/22/19 1942 Freddy 3034 10/22/19 Northwes Freddy $1, 141 10/23/19 1620 Gigi 9710 9 10/23/19 Northwes Chin $725 10/24/19 8610 10 10/24/19 West Chir 5222 10/25/19 5148 11 10/25/19 West June $1,038 10/26/19 2178 12 10/21/19 Northwee Chin $154 13 10/22/19 Northwee Gigi $205 14 10/23/19 Southwe Gigi 5895 15 10/24/19 W Chin $1,254 4) Region/SalesRep June Chin Freddy Gigi Total Sale 16 10/25/19 Northwes June $596 Northwes 17 10/24/19 Southwe Gigi $799 Southwest 18 10/24/19 Northwes Gigi $651 West 19 10/24/19 West June $1,235 Total Sales 20 10/24/19 Southwe Chin $684 21 10/25/19 Northwee June $127 22 10/26/19 West June $269 23 10/25/19 Southwe Chin 5739 24 10/26/19 West Gigi $1,201 25 10/26/19 Northwes June $546 26 10/26/19 Northwes Chin $162 27 10/20/19 West Gigi 5620 28 10/20/19 Northwes Gigi $484 29 10/20/19 West Freddy $376 30 10/20/19 Northwee Freddy $1,141 31 10/20/19 Northwes Chin $725 32 10/20/19 Wes Chin $227 33 10/20/19 West June $1,038 34 10/21/19 Northwes Chin $154 35 10/21/19 Northwes Gigi 5205 36 10/21/19 Southwe Gigi 5895 37 10/21/19 West Chin $1,254 38 10/22/19 Northwes June $596 39 10/24/19 Southwe Gigi $799 40 10/24/19 Northwee Gigi $651 41 10/24/19 West June $1,235 42 10/24/19 Southwe Chir $684 43 10/24/19 Northwes June $127 44 10/24/19 West June $269 45 10/25/19 Southwe Chir $739 46 10/25/19 West Gigi $1,201 47 10/25/19 Northwes June $546 48 10/25/19 Northwes Chin $162