Calculate the PVB of $4-$year bond with a nominal of $140000$ PLN$,$ interest $6\%$ pa$,$ coupons paid each $4$M and YTM at $8\%$ if there is convexity of $4-$year bond with nominal $1000$ PLN$,$ interest $8\%$ pa$,$ coupons paid quarterly and YTM $12\%$ pa$,$ if it is $2$ years till maturity.