Please help to Question B only , thank you

NEWS 2 (RTHK, 24 July 2022)2 Tenants overcharged despite rent control law: SOCO A grassroots organisation on Sunday urged the government to strengthen enforcement of the tenancy control ordinance on subdivided ats, saying the law hasn't barred landlords from overcharging tenants for utilities. The legislation, which came into effect in January this year, stipulates that landlords are not allowed to charge unreasonable water and electricity fees from tenants during the lease. However, the Society for Community Organisation (SoCO) said it surveyed 550 tenants of subdivided units last month and found that over 70 percent of them are still being overcharged. A tenant sumamed Chan said she could only turn on her air-conditioner sparingly amid the current heat wave. \"1 would wake up in the middle of the night and turn off the air-conditioner. I wouldn't turn it on for too long because the bill is too expensive. Even with the window open, the wind is hot. There is no cool air.\" But Chan said she wouldn't file complaints even if her landlord broke the law for fear of being kicked out. The group's deputy director, Sze Lai-shan, said the government should step up enforcement by carrying out more inspections. \"Also, they should take the initiative to help to install individual electric meters for each household, and even [make it] a legislation. Otherwise the tenants will suffer," she said. Sze also called on the government to provide more subsidies and affordable housing to help those living in subdivided units. Study the extract above and answer the following questions. (a) Explain why governments implements rent control. (5 marks) (b) Use the demand and supply model to illustrate the imposition of a rent control and analysis its effect on market outcome. (20 marks)