Determine Whether the Given Argument Is Valid or Invalid

question 149

Essay

determine whether the given argument is valid or invalid. If it is valid, provide a derivation of the conclusion from the premises. If it is invalid, provide a counterexample.
-1. (∃x)(Px • Qx)
2. (∃x)(Px • Rx)
3. (∀x)(Qx ⊃ Sx)
4. (∀x)(Rx ⊃ Tx) / (∃x)(Px • Sx) • (∃x)(Px • Tx)

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Definitions:

Foreign Exchange Risk

The potential for financial losses due to changes in exchange rates affecting the value of foreign-currency-denominated assets and liabilities.

Foreign Exchange Gain

Foreign Exchange Gain arises when a currency transaction results in receiving or paying fewer units of the home currency than initially anticipated due to exchange rate movements.

Option Strike Price

The predetermined price at which the holder of an option can buy (in the case of a call option) or sell (in the case of a put option) the underlying security.

Spot Rate

The current market price used for immediate settlement of a currency, security, or commodity transaction.