#### Answer

a) $C=200x+60000$
b) $R=450x$
c) $240$ desks, $R(240)=\$108000$

#### Work Step by Step

a) Here, the cost is the fixed cost. This means $\$ 60000$ plus $\$ 200$ per desk.
Hence, $C=200x+60000$
b) Revenue $=\$450$ per Desk
Hence, $R=450x$
c) The break -even point occurs when profit is equal to zero, that is, $R=C$
Thus,
$P=200x+60000$
$0=200x+60000$
Hence, $x= 240$ desks
At this point, revenue is:
$R(240)=450*240=\$108000$