oracle - Updating Multiple Rows in PL/SQL -

i trying update multiple rows in plsql block. possible update several rows single update statement.
example, use following code:

update ordertable set cost = 400 , shipping = 8, , tax = .06; 

is acceptable?

the syntax of update wrong. possible update more 1 row 1 statement.

update ordertable set cost = 400, shipping = 8, tax = .06; 

this update all rows in table ordertable. add restrictions change rows.

update ordertable set cost = 400, shipping = 8, tax = .06 cost < 100 or shipping >9; 

most tools report rows updated output or feedback. can check rows updated prior running update, using restriction in select statement.

select * ordertable cost < 100 or shipping >9;