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Fair Value Measurements (Tables)

9 Months Ended

Jan. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The Company determined the fair value using the Black-Scholes option pricing model with the following assumptions:

		January 31, 2021				January 31, 2020
Dividend rate			0.0	%			0.0	%
Risk-free rate			0.07% - 0.08	%			1.5	%
Expected life (years)			0.5 - 0.8				1.3 - 1.4
Expected volatility			146.1	%			109.8% - 130.1	%

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- Definition

Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

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