Consider the following worksheet:
(a) In a spreadsheet, every formula starts with a/an ................. sign.
(b) Write the formula to calculate the amount for Glue stick. (Amount is calculated as Price $\times$ Quantity)
Complete and balance the following chemical equations: (a) \[ 2MnO_4^-(aq) + 10I^-(aq) + 16H^+(aq) \rightarrow \] (b) \[ Cr_2O_7^{2-}(aq) + 6Fe^{2+}(aq) + 14H^+(aq) \rightarrow \]