$2\mathrm{.}10$ Two forces are applied as shown to a hook support. Knowing that

the magnitude of $P$ is $35$ N $,$ determine by trigonometry $($a$)$ the

required angle a if the resultant $R$ of the two forces applied to the

support is to be horizontal, $($b$)$ the corresponding magnitude of $R.$

Fig. P$2\mathrm{.}10$